In recent years, a broadcasting organization and the like are considering a hybrid service of combining broadcasting and communications networks (hereinafter, referred to communications) from the standpoint of enhancing a broadcast service by utilizing communications. As an example of a technology for providing such a hybrid service, Non-Patent Literature 1 discloses the following technology called Hybridcast™. Hybridcast uses a receiver that receives broadcast programs transmitted via a broadcast wave and contents transmitted via a network, and synchronizes and presents the received programs and contents.
With this technology, the receiver receives a broadcast video transmitted by broadcasting and an additional video transmitted via a network, and displays a single combined video by arranging the broadcast video on the right and the additional video on the left. As a result, it is possible to display the video that is wider than the video transmitted by broadcasting, for example. Further, compatibility with receivers that do not support the above technology (hereinafter, such receivers are referred to as “legacy receivers”) can be maintained since the legacy receivers can receive and display a video transmitted via a broadcast wave.